Posts Tagged ‘KISS’

April 25 on the Mohawk

Saturday, April 25th, 2009

Let’s see, a forecast for warm air, cold water, and no wind. That translates into fog. Thick fog. Driving down to the shore, the fog quickly slowed traffic to a craw. As we slowly headed out the inlet we could barely see both sides. Once away from the beach, the fog cleared and the sun came out.

Our destination for the day was the Mohawk. The wreck lies in 75 ft of water which allows for some longer bottom time. Danny had us tied into the stern on the starboard side. With only a slight wind and minimal current, the anchor like dropped nearly straight down to the wreck. Reports came back of 44 degrees, and and only 15 ft of vis. That leaves the camera is out. I jumped in to see what the winter storms had done to the wreck. Franky jumped in with Franky Cam 2.0. The addition of a chin strap to prevent loss of the camera.

Sean left his pole spear by the anchor for me, but I left it in favor of just having fun. Perhaps the sun was up higher in the sky, but the vis looked more like 25-30. I swam down the port side inspecting an nook with evidence of excavation. There were a few small bugs, but no keepers. Many holes were occupied by eel pouts rather than lobsters. A few seabass popped up here and there, and gonfiabili a number of smaller tog. Up by the pilot house there were a few nice size tog hanging out. There seemed to be a lot of yellow sponge laying in the debris field. Here and there whole sections of the wreckage were covered with large anemones, outstretched in the still water.

Clearing the wheelhouse, I heard engines off in the distance. Time to get off the wreck. On the way back to the stern, I inspected pieces out in the sand. Again, the holes were mostly empty, with only shorts left. Divers brought up winter flounder, tog Seabass and pictures.

The breeze had picked up enough to blow out the fog, and we had a smooth ride home.

The Independence is heading out May 2 and 3. Contact Capt Dan for spots @ 732-232-7878

What is a Rebreather?

Tuesday, January 13th, 2009

Many people see my dive gear, and ask “What newfangled contraptions is that”? Ok, maybe they don’t use the word “newfangled”, but you get the point. I dive a Closed Circuit Rebreather (aka CCR). While people think of these as “new”, they actually predate the gear we consider standard SCUBA (also called Open Circuit or OC).

History: Early rebreathers were used not for diving, but for escape. Mines and Submarines both presented situations where a compact breathing device was needed to allow crews to escape to safety. Theses were developed back in the early 1900, and produced in quantity by 1910. Open Circuit SCUBA was not commercially available until the mid 1940s.

How do they work: Let’s start with a quick review of metabolism. Our cells take in food and Oxygen (O2). These are combined to produce energy, but have a toxic byproduct of Carbon Dioxide (CO2). Our Cardiopulmonary system takes some of the O2 from the air we breath, and distributes it to our cells. At the same time it takes the CO2 generated bouncy castle for sale by our cells, and releases it into the air that we exhale. The O2 and CO2 exchanged by our lungs is actually a small percentage of the volume of gas that we breath (about 3%-5%).

On Open Circuit, when a diver inhales, the regulator provides the diver with gas (usually air) at same pressure as the surrounding water. When we exhale, the gas is vented out into the water producing the column of bubbles associated with diving.

When a CCR diver exhales, the gas is vented into a flexible chamber called a counter lung. Within the Rebreather, O2 is added back into the gas, and it is passed through a “scrubber” which removes the CO2. We then inhale the same gas which again contains the proper O2 percentage.

With OC 95% of the gas we exhale has not been affected by our respiration. It is not used. It is wasted. On CCR, this 95% is recycled, cleaned of CO2, enriched with O2, and breathed again. This allows us to make use of smaller tanks, as our O2 consumption does not change with depth.